1. Field of the Invention
This invention relates generally to devices using the principle of predictable movement when equal pressures applied to unequal areas result in unequal forces. Called a flush valve or flushometer this device also relates to devices for metering a predetermined volume of liquid to a fixture.
2. Description of the Prior Art
A common problem with known type devices using an orifice and check valve to establish the rate of valve opening and closing is that the conventional orifice and check valve are in contact with the source of liquid or gas in the mainline and therefore are subject to malfunction due to blockage of the orifice by dirt or other contaminants contained therein.
Another problem with known type devices is that the handles for concealed flush valves vary as to wall thickness of the establishments in which they are to be installed and therefore cause many problems in ordering and installing therein.
A further problem is that by having many models and types of these devices, commonly called flush valves, and different body patterns thereto because of handle locations the purchaser of said flush valve may become confused therefore complicating his selection and/or installation of the proper type flush valve for his establishment. This is very important for much money and time may be wasted if a person were to order and/or install the wrong type of flush valve for his particular purpose or establishment.
A still further problem with the aforesaid flush valve is that the bodies and parts are cast in brass which requires much machining and also has a tendency to keep the weight and cost of production high which also increases the cost to the purchaser and keeps the cost of shipping high.
Known prior art patents which may be pertinent to this invention are as follows:
U.S. Pat. No. 2,000,002 PA1 U.S. Pat. No. 2,270,259 PA1 U.S. Pat. No. 2,282,755 PA1 U.S. Pat. No. 2,734,712 PA1 U.S. Pat. No. 2,811,167 PA1 U.S. Pat. No. 2,872,150 PA1 U.S. Pat. No. 2,900,163 PA1 U.S. Pat. No. 3,020,925.
None of these known prior art devices offers the new and unique features of the invention disclosed herein. For example, U.S. Pat. No. 2,000,002, Control Valve For Gas Burners, 1932. This device controls the flow rate and downstream pressure of gas and is responsive to a pressure and/or a temperature control device which varies the pressure in a pilot chamber causing a position change in the main valve. This design is typical in gas control valves currently furnished. The orifice and check valve are incorporated to establish the rate of valve opening and closing. It is not important to note that the orifice and the check valve are in contact with the mainline gas source hence subject to malfunction due to contaminants contained therein. The subject valve of this invention incorporates a similar hydraulic principle plus the unique and distinct feature of captive fluid in contact with the orifice and check valve. Being captive the fluid quality is controlled thus eliminating the contamination mentioned above, and, thus providing a suitable valve for contaminated liquids, and further through material selection suitable for corrosive liquids.
U.S. Pat. No. 2,811,167, Pilot Operated Shut Off Valve, 1957. This device uses the well known principle of predictable movement when equal pressures applied to unequal areas result in unequal forces. The main valve is either open or closed as established by the liquid level. The use of multiple control diaphragm, floats, etc. appears to be for safety reasons. This is not a metering valve as is disclosed herein.
U.S. Pat. Nos. 2,282,755, 2,900,163 and 3,020,925 are all devices based on the above mentioned principles and actuated by pressure, or temperature or combined pressure/temperature.
U.S. Pat. Nos. 2,270,259, 2,734,712 and 2,872,150 are liquid metering valves for plumbing fixtures. Federal specifications described them as flushometers, the plumbing industry as flush valves. This is the type of device of this invention, and all true flush valves including the one disclosed herein, meter a predetermined volume of liquid to a fixture. Known type flush valves use a pilot chamber and refill orifice principle with source water passing through the orifice which is quite small and vulnerable to stoppage. The subject invention valve eliminates this problem and hence is suitable for a wide range of liquids.
The subject valve aspires to be modern with economic features, namely, most known valves require a plurality of body patterns, requiring different manufacturing techniques and equipment, and greatly increasing stocking requirements. The valve disclosed herein has a single body construction with greatly simplified manufacturing and storage/stocking requirements. Also the disclosed operating mechanism is simple and extremely flexible in installation.
The design of the valve of this invention also permits manufacturing from drawn and rolled materials with a minimum of machining and with low weight and cost. The one single body structure will fit all needs and supply all conditions.